Fault location in underground systems through optimum-path forest

In this paper we propose an accurate method for fault location in underground distribution systems by means of an Optimum-Path Forest (OPF) classifier. We applied the Time Domains Reflectometry method for signal acquisition, which was further analyzed by OPF and several other well known pattern recognition techniques. The results indicated that OPF and Support Vector Machines outperformed Artificial Neural Networks classifier. However, OPF has been much more efficient than all classifiers for training, and the second one faster for classification. © 2011 IEEE.

Networked control system for the guidance of a four-wheel steering agricultural robotic platform

A current trend in the agricultural area is the development of mobile robots and autonomous vehicles for precision agriculture (PA). One of the major challenges in the design of these robots is the development of the electronic architecture for the control of the devices. In a joint project among research institutions and a private company in Brazil a multifunctional robotic platform for information acquisition in PA is being designed. This platform has as main characteristics four-wheel propulsion and independent steering, adjustable width, span of 1,80m in height, diesel engine, hydraulic system, and a CAN-based networked control system (NCS). This paper presents a NCS solution for the platform guidance by the four-wheel hydraulic steering distributed control. The control strategy, centered on the robot manipulators control theory, is based on the difference between the desired and actual position and considering the angular speed of the wheels. The results demonstrate that the NCS was simple and efficient, providing suitable steering performance for the platform guidance. Even though the simplicity of the NCS solution developed, it also overcame some verified control challenges in the robot guidance system design such as the hydraulic system delay, nonlinearities in the steering actuators, and inertia in the steering system due the friction of different terrains. Copyright © 2012 Eduardo Pacincia Godoy et al.

Practical comparisons among electronic energy meters, a precision energy meter and IEEE1459 for reactive energy measurements, under unbalanced and non-sinusoidal conditions

This paper presents a practical experimentation for comparing reactive/non-active energy measures, considering three-phase four-wire non-sinusoidal and unbalanced circuits, involving five different commercial electronic meters. The experimentation set provides separately voltage and current generation, each one with any waveform involving up to fifty-first harmonic components, identically compared with acquisitions obtained from utility. The experimental accuracy is guaranteed by a class A power analyzer, according to IEC61000-4-30 standard. Some current and voltage combination profiles are presented and confronted with two different references of reactive/non-active calculation methodologies; instantaneous power theory and IEEE 1459-2010. The first methodology considers the instantaneous power theory, present into the advanced mathematical internal algorithm from WT3000 power analyzer, and the second methodology, accomplish with IEEE 1459-2010 standard, uses waveform voltage and current acquisition from WT3000 as input data for a virtual meter developed on Mathlab/Simulink software. © 2012 IEEE.

The emergence of Latin multinationals

Includes bibliography

Imagens multitemporais ALOS/PALSAR baseada em orientação a objeto na discriminação da cobertura da terra

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Quantificação da resoluçao do sistema SPECT-CZT através do uso da função de transferência modulada (MTF)

Pós-graduação em Biologia Geral e Aplicada - IBB

O controle concorrencial dos atos de concentração como instrumento de implementação de política pública estatal

Pós-graduação em Direito - FCHS

Estética da mercadoria e obsolescência: um estudo da indução ao consumo no capitalismo atual

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Diagnóstico de ambiência na sub-bacia do Rio das Pedras, Municipio de Itatinga – SP, visando o planejamento sócio conservacionista

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Trade and investment flows between the Caribbean and the rest of the hemisphere in the context of the FTAA

Includes bibliography

The impact of privatisation on the banking sector in the Caribbean

Includes bibliography

Formação de professores e experiência formativa

Pós-graduação em Educação - FCT

A história do mental de Lucien Febvre: uma complexidade reflexiva

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Os processos de comunicação e mediação da informação em uma indústria de alta produtividade do setor sucroalcooleiro no estado de São Paulo

Pós-graduação em Ciência da Informação - FFC

Tempo, espaço e corpo na representação espacial: contribuições para a educação infantil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)